Electric system.



F. M. SLOUGH.

ELECTRIC SYSTEM.

APPLICATION FILED NOV. 27. 1912.

Patented Nov. 14, 1916.

,Wzirzcsse 31d. SLOUGI-l, OF ELYEIA, OHIO, ASSIGNOR TO THE GARFGRL MANY) "hCTULJiFG' CQTVIPAIIY, OE ELYRIA, OHIO, A CORPORATIQN F (EH16.

ELECTRIC SYSTEM.

Specification of Letters Patent.

Patented Nov.

To aZZ whom it may concern Be it known that-l, FRANK M. SLOUGH, a. citizen of the United States, residing at Elyria, in the county of Lorain and State of ()hio, have invented certain new and useful Improvements in Electric Systems; and I do hereby declare the following to bea full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

My invention relates to electric systems, and especially to systems adapted for use in isolated places or in places where the attendant is partially or totally unskilled in the art of managing such plants. F or example, in lighting systems adapted to be used in country residences, or upon farms or other isolated places Where there is no attendant, or where those overseeing the operation of the plant are unskilled in the handling of such apparatus, I aimto make the operation of the plant automatic, so that very little attention will be required to keep the apparatus in working order.

in general, my invention relates to immovements in the system illustrated, described and claimed in my application #709,137, filed July 13th, 1912, also in my application #704,505, filed June 19th, 1912', such applications describing the needs of such a system and the faults of the systems constituting the prior art. In operating these automatic systems, it has been found that one of the difiiculties experienced was in starting the explosive engine by means of the dynamo-electric machine operated by current from the storage battery, said dynamo-electric machine being so operated as a It has been motor to crank said. engine. found that the eli'ort necessary in order to start the cranking of the engine against the internal load in the engine cylinder is sometimes so great as to so overload the dynamoelectric machine that the same fails to start to crank the engine.

I provide means inthe present invention to release the internal load of the engine before starting to crank same, and l also provide means for restoring the compression releasing device to its normal position after a certain length of time, or after the engine and dynamoelectric machine have gathered sufiicient momentum to'carry on the cranking of the engine.

It has also been found in these automatic systems, that due to the fact that they require so little attention, very little attention is given them. Therefore, it has been deemed necessary to provide some means to prevent the working parts of the engine and the dynamo from becoming overheated. l have, therefore, provided in this invention devices for shutting down the charging mechanism if any part of same should become overheated. Another difiiculty experienced with these systems has been that the attendant neglects to keep the lubricating oil tank filled; also Where water is used for cooling the engine cylinder, it has been found that the Water tank also is neglected.

I provide means in the present invention for shutting down the charging mechanism after a predetermined length of time if the water in the water tank or the lubricating oil in the oil tank has reached a predetermined low point, and I also provide an. alarm signal for indicating that something is wrong with the charging mechanism, this alarm signal being operated for a certain length of time, after which it is cut ofit I have provided also in this invention, controlling means having certain advantages over the controlling means employed in the prior art, also in my other applications, and in the latter case, especially so under some conditions.

in my present invention a voltmeter relay is'provided for controlling the charging operation under ordinary conditions; however, it is found that while a voltmeter does very well for this purpose, still it is conceded that a hydrometer immersed in the electrolyte of the storage batte y will, under certain circumstances, show more truly when the storage battery has become exhuustech'and more particularly will it show in a more accurate manner when a charge has been completed.

Under ordinary conditions of operation or" the system as herein described, it is expected to control the charging operations for the greater part of the time with a voltmeter relay, the same being so adjusted as to start the charge of the battery sometime before the same has become totally exhausted, and

also to cut off the charging operation before the battery is quite fully charged. It is recommended by many of the storage battery manufacturers that occasionally a storage battery should begiven a full charge, and as same cannot be accurately determined by a voltmeter indication, I herein provide alternative means for cutting off the charging invention.

operation, consisting of a hydrometer immersed in the electrolyte of the storage battery, which hydrometer will cut off the charging operation whenever a certain predetermined density of the solution is produced by the charging of the battery.

Other objects of my invention and the invention itself will be better understood from a description ofthe embodiment of my invention illustrated in the drawings.

Figure 1 illustrates an embodiment of my Figs. 2 and 3 show modifications of certain features of Fig. 1.

Referring now to the drawing and to. the particular embodiment of my invention illustrated in Fig. 1, at P is shown a prime mover, such as an explosive engine and at D a source of current, such as a dynamoelectric machine for charging, an accumulator shown at B, which here consists of a storage battery. I prefer to use a gas or gasolene engine as a prime mover, although any kind of explosive engine would serve the purpose of my invention equally as well, such as a kerosene engine, or an engine operated with producer gas, alcohol, etc. At

.E I have shown a number of electro-responsive devices, such as incandescent lamps, which are adapted to be energized by current from the accumulator at B. Then the accumulator is first connected to the dynamo, the same is driven as a motor by the current from the battery, this being in virtue of the fact that a shunt wound dynamo will operate as a motor without changing the direction of the rotation or'the connections of the leads to the armature and fieldcoils, and when so driven, it starts the prime mover through some power transmitting means, such as pulleys C and F and an inter-connecting belt A. After the prime mover is operated by the dynamo for a certain length of time, which will vary considerably, and which will not require as long a time in warm weather as in cold weather, the same is caused to operate under its own power and will then actuate the dynamo which will generate current to charge the accumulator. At G I show an electro-responsive device which maybe a voltmeter, a marginal relay, or other suitable device of this character. H, L, M, N and 0 are circuit controlling means, such as electromagnets whose functions will be described in the description of the operation. R isa time controlled element, such. as a thermal device, here shown as consisting in part of a retric machine D. T is an eleotromagnet adapted to releasethe compression in the engine cylinder, so as to enable the dynamo to more easily start to crank the engine. Y and Y are floats in the fluid containing tanks, not shown, which contain the supply of water for cooling the engine cylinder and lubricating oil for the mechanical system of the charging mechanism. These floats are adapted to operate electric contacts when the supply of fuel in the tanks has become depleted. Z and Z are thermostats arranged in proximity to the parts of the charging mechanism which might become over-heated. It can be seen, therefore, that even if the devices Y and Y should fail to operate and to shut down the charging mechanism whenever the supply of fluids was exhausted, that the devices Z and Z would furnish a check ,upon the action of the aforesaid devices, shutting down the charging mechanism whenever the heating, due to the lack of said fluids, becomes excessive. These'devices Y and Y and Z and Z may be increased innumber according to the needs of the particular type of charging mechanism used.

In Fig. 2 is shown a hydrometer operated electric switch for shutting down the charging operation whenever it is desired to charge the battery more fully than would be the case were dependence placed alone upon the marginal relay G.

In Fig. 3 is shown a means of controlling the charging operation entirely with the hydrometer whenever it is considered advisable to do this.

The embodiment of my invention and the various parts thereof, as well as other func tions, will be clear from a description of the operation which is as follows :The accumulator B will be normally connected to the electro-responsive devices E through the conductors 4, 1, 2 and 3. whereby they will be actuated *when turned on. The electroresp'onsive device G is normally connected across the battery from negative battery through the conductors 5 and 6 variable 'resistance rlever arm of same l-concuits being merely used for the sake of clearness, and not because of any necessity for so operating the system. Also, in the description following, it is to be understood that the terms ground battery and positive battery are to be used synonymously.

The member 11, which is here shown as a movable needle, will be" moved under the joint control of the spring S and the electromagnet winding W, the influence of the winding varying according to the condition of charge in the accumulator, such for example, as the variations of the voltage therein, and will be so arranged that for a predetermined condition, the member 11 will engage the contact 12, closing a circuit as follows, it being understood that during the operable condition of the system the switchingkey K is depressed :positive pole of battery-contacts 13 and 14 of the switching key K conductors l5 l6 22 movable needle 1lcontact 12conductor 17-.winding 18 of the relay 0-conductors 195to negative battery, thus drawing up the armature of the relay 0. When this takes place, the armature 20 makes a connection with contact 21 of the relay U, shunting the circuit comprising conductors 1622movable needle 11contact 12 and conductor 17, thus maintaining the supply of current through the winding 18 of the relay 0 independent of the contact 12 with the movable needle 11. At the same time, the armature 23, closing a contact 24, completes a circuit from negative battery-contacts 25 and 26 of the switching key K-conductor 27armature 23 and contact 24 of the relay @conductors 28-29803lwinding 32 of the relay M to ground, or positivebattery, thus operating the relay M. Also a circuit is closed to 0pcrate the compression release T as follows negative batterycontacts 25 and 26 of the switching key Kconductor 27-armature 23 and contact at of the relay O-conductors 2S3334lwinding 85 of the compression release Tconductor 36spring contacts 37 and 38 of the time element device l t-wonductor 39contact 40 and armature d1 of the locking relay Nconductor 42 to positive battery, thus operating the compression release T of the engine P.

Relay M, being operated, attracts its armatures 1043and 44:. being attracted, breaks a connection with the contact 9 and ceases to shunt the variable resistance r as before. Therefore, a circuit of higher resistance will be provided for the electro-responsive device G as follows negative pole of battery-conductors 5 variable resistance r movable lever 1 thereof, conductor 7-winding VJ of the electroresponsive device Gconductors 8- 45 to the movable lever l of the variable resistance r, variable resistance rconduc tor to positive battery This added resist- Armature 1O ance in the circuit of the device G is designed to cause the device G to require a higher voltage to operate it to make the contact t? than would otherwise have been the case.

The variable resistances r and r can be so adjusted as to operate on any voltage of battery, and also to cause the electro-responsive device G to exercise such a control over the charging mechanism as will enable the charging to be carried on for a longer or shorter time, as may be desired; also these resistances will be varied as may be neces sary in colder or in warmer weather, so as to produce a given result, it being a fact that in charging a storage battery in very cold weather a higher voltage reading will be obtained at the finish of the charge, for instance, than is the case in warmer weather. For example, the lever arm 1 might take a certain position when the temperature is 70 Fahrenheit, but if the temperature were zero degrees, then the lever arm 1 would be moved so as to interpose a greater resistance between the Conductors as and 46 than in the former case.

The armature 10 being attracted as before stated, will also close the contact 47 of'the relay M, thus closing the following circuit :positive battery-armature 10 and con- 9 tact 47 of the relay Mconductors 48%9- relay winding 50 of the relay L-ronductor 51relay winding 52 of the relay El-con- (luctors 533328contact 24 and armature 23 of the relay Oconductor 27con- 10o tacts 2G and 25 of the switching key lto negative battery, thus operating relay-H, which closes the following circuit :negativc pole of accumulator Bconductor 5'llow resistance winding 55 of the relay Lconductor 56contact pieces 5758and 59 of the relay l-lconductor 60 to the negative pole of the dynamo-electric machine l) through the field winding and armature winding 61 in multiple with each otherpositive pole of dynamo-conductor 62 to positive pole of the battery.

The compression release T, having been operated as has been previously described,

the accumulator B starts. to cause the operar- 1Z3 winding 65 and vibrator contacts 66 and 67 of the spark coil X, conductor 68 of the mechanical timer on the engine, which timer makes an electric contact whenever it is desired to produce a spark in the engine cylinder in the usual manner; this timing device being well known is not shown. The circuit is then continued through the timing device to the frame of the engine 69, which is connected to a conductor 70, leading to a tap 71, which may be, as shown, intermediate of the terminals of the accumulator B. This tap is so madethat only the required amount of battery voltage necessary to operate the spark coil is obtained therebya This, in practice, is usually about six volts; consequently, this is generally made so as to include three cells of storage battery in the ignition or sparking circuit, as previously described. Therefore, the vibrator X is operated, and by means of a secondary winding 72 on the spark coil K through conductor 73spark plug 7 4the frame of the engine (SQ-and conductor 75 back to the secondary winding of the spark coil, a spark is produced in the engine cylinder whenever the timing device, as previously mentioned, causes a contact contained therein to be made.- The engine being cranked, as previously described, and the spark being caused in the engine cylinder at the proper time, as has been described, and fuel being admitted to the engine by mechanical suction in the well known manner, the engine will soon start to drive the dynamo, operating under its own power. The dynamo, upon being operated, will start to charge the storage battery over the following circuit :nega-' tive pole of the dynamo-conductor (SO-contacts 5958 and 57 of the relay Hconductor 56 and winding 55 of the relay Lconductor 54 to the negative pole of the accumulator Bconductor 62to positive pole of the dynamo; also current will flow from the positive and negative poles of the dynamo to energize a magnet Q so as to allow lubricating oil to flow from the oil tank V. This circuit will be as follows:positive pole of dynamo Dconductor 76-winding 77 of the magnet Qconductor 78-to negative pole of the dynamo. It is, therefore, plain that the magnet Q Wlll be operated, thus allowing lubricating oil to flow to the parts of the explosive engine whenever needed, as long as the charging mechanism is operated, and the supply will be automatically cut off whenever the charging mechanism is shut down. Also at the time the relay M is operated, a circuit is completed as follows positive pole of battery to armature l0-contact 47 of the relay M-conductors 4879 contact 80 and armature 81 of the locking relay Nconductor 82 and the heating winding 83 of the thermal time element device lftconductors 8=l852928 contact 24 and armature. 23 of the relay Oconductor 27contacts 26 and 25 of the switching key K to the negative battery. This causes the heating winding 83 to so heat up the dissimilar elements 86 and 87 which are riveted together at various points along their length and causes a longitudinal expansion of the same. Inasmuch as the materials for these two elements are so chosen that the upper one 87 has a greater rate of expansion under the influence of heat than the lower element 86, it is obvious that the contact 88 will move toward the contact 89, said movement being due to a bending or warping of the two riveted elements. It is obvious also that this will be a gradual process and that it will take some time before the contact 88 makes connection with the contact 89. The contacts 37 and 38 are also shown carried by this device, and are so adjusted that contact 37 will break away from contact 38 some time previous to the 'moment when contact 88 makes connection with contact 89. The

circuit involving contacts 37 and 38 has been,

previously described and concerns the operation of the compression release T, so it is needless to go into the operation of this circuit again.

When contact 88 makes connection with contact 89, here shown adjustable in relation to contact 88, a circuit is closed as followspositi"e batteryriveted member 90 consisting of the dissimilar elements 86 and 87 contact 88 carried therebycontact 89conductor 91winding 92 of the locking relay Nconductors 9385-29-28 contact 24: and armature 23 of the relay 0- conductor 27contacts 26 and 25 of the switching key K'-to negative battery. This .tive batteryconductor"95winding 94 of the locking relay Nconductor 96contact 97armature 81 of the locking relay N conductor 82the resistance winding 83 of the thermal time element device Rconductors 98 2928contact 245 and armature 23 of the relay O-conductor 27-contacts 26 and 25 of the switching key K to negative battery. It is, obvious, therefore, that so long as the relay 0 remains operated, the locking relay N when once operated will remain so. The resistance of the winding 94 of the locking relay N is purposely made so high that insuflicient current to cause any appreciable heating of the resistance winding 83 of the thermal time element device R will be passed through the same. Therefore, so faras the heating of the thermal time element device R is concerned, when the locking relay N is operated, it can be considered that the heating of the thermal device is discontinued,

the heating winding of the same furnishing merely a convenient path for current for the locking winding 9%. of the locking relay N.

l find that in order to produce very good results with the thermal relay R that the resistance of same should be so proportioned that about twenty or thirty watts of energy will be converted thereby into heat. However, this value could be modified depending upon the size, form and general make-up of this device as might be used in practice. Using a resistance of 1000 ohms for the winding ill of the relay N and having an accumulator of thirty volts to operate the circuits mentioned, it can be seen that when connected in series with the winding ill of the locking relay N only about .02 of a watt will be dissipated as heatin the heating winding 83, so that, as has been previously explained, the effect is negligible.

ll hen the locking relay N has been operated, as has been described, the armature ll is also attracted, breaking connection with a contact 40 which opens up. the circuit of the compression releasing device T, which has previously been described. Therefore, the compression release T cannot again be operated as it otherwise would be upon the return of the thermal time ele nientdevice to its original position upon the actuation of the locking relay N and )BTOLG the successful completion of the charging operation as would otherwise be the case. The armature ll, upon being attracted, will also make a connection with a contact 99, closing an enier 'ency circuit for the purposeof shutting down the charging mechanism, and for the purpose of rin ing an alarm bell in case the charging operation has not yet started.- lt will be understood at this pointthat the charging mechanism has now had plenty of time to begin to operate to charge the storage battery, the thermal time element device it requiring a period of several minutes for its operation. I wish to say also in this connection that in order to insure plenty of time for the charging mechanism to get started, which requires a longer time in winter or cold weather than in summer, the thermal time element device It is so constructed as to allow more time in cold weather before the operation of the locking relay N than it would in warm weather. This is on account of the fact that of the two riveted members 87 and 88, comprising the moving system of the time element device R, the member 87 is much more affected by heat or the lack of heat than the member 88; consequently, in cold weather it will contract more than will the member 88, withdrawing from the Contact piece 89 to a degree depending upon the degree of coldness, Therefore,

if the thermal device were to be operated under this condition, it would talze longer for it to absorb enough heat to move it greater distance in order to make contact with the member 89, as has been previously stated.

Now to return to the descriptionoi emergency circuit as closed by the loclrlne" relay N, l would say that this circuit controlled largely by a relay L, whose functions will now be descri ed. l I composed of two windings, one of l sistance and one of very low resistance. The high resistance winding 50 is independent of the main charging circuit t e current through the same is always unidirectional. The low resistance 55 is in series with the circuit and when the dynamo-electric machine is operating to charge the storage battery. "he magnetic efiect of this low resistance r ing is accumulative with the effect or the winding 50. However, when the accumulator is operating to drive the dyna 0- electric machine as a motor in order to crank the engine which operation takes place previous to the charging operation,

the effect of the winding 55 is differential with respect to the winding 50. Therefore, in the latter case, instead of being attracted, the armature will take a released position, and whenever in the normal or released position, shows that the mechanism is not operating so as to char e the storage battery, and in the latter case, a contact is made with armature 100 by a contact piece 101, thus completing the emergency circuit, which, as has been previously mentioned, is also closed at 99 after the operation of the locking relay N. This emer ency circuit is as follows;positive batteryconductor t2armature ll-contact 99 of the locking relay Nconductor 102armature 100contact 101 c the relay li-conductors 103-10 iwinding 105 of the differential relay Mconductors 106 10'Z'302928c0ntact 24 and armature 23 of the relay ()c0nductor 27-contacts 26 and 25 of the switching key K to negative battery. The winding 105 of the relav M being so connected as to oppose the action of winding 32 of this relay, will cause a release of the several armatures of this relay, thus disconnecting relay H by ie breaking of contact 47 with armature 10, which opens the charging circuit at 57 and 59. The primary winding of the spark coil X is also disconnected by the breaking of contact 63 with armature 13, thus cutting ed the ignition system of the engine. Also armature 4 will be released making a contact 143 which closes an alarm circuit which will now be described.

I haveshown at a a visual alarm device, and at 110 a switch member, which is adapted to close any one of several contacts, so that the alarm device 6 will be connected to the circuit in any one of several ways. We will assume in this description that the switch member 110 is making contact with the contact piece 108, so as to connect the alarm device 6 in multiple with the differential winding 105 and relay M. It may sometimes be more desirable to place a visual signal in circuit in this manner and connect the audible signal in the place. of the visual signal a. This is left to the user to decide, either method of operation having its own advantages.

If the switch member 110 were to be con nected with contact piece 109, this would simply place the two alarm devices in multiple one with the other. lVhen the emergency circuit is closed as has been described, releasing the armatures of the relay M and more particularly releasing the armature 44 which thereupon makes contact with the contact piece 143, an alarm circuit will be .provided as follows :-positive batterythe movable element 86 of the thermal device Rcontact piece 89conductor 144contact 143armature 44 of the relay M alarm device aconductors 11110730 29-28contact 24 and armature '23 of the relay Oconductor 27contacts 26 and 25 of the switching key K to negative battery, thus operating the alarm device a. This alarm device will continue to operate as long as the movable element of the thermal device R continues to make contact with the contact piece 89. This ordinarily will last for several minutes, and by .proper proportioning of-these parts, and by making cer-- 111-112alarm device b-conductor 113 switch lever 110'contact piece 108 of the switch I) and conductor 114, the-alarm device b will operate and continue to operate as long as the emergency circuit, previously described, is closed. This will last until the attendant releases the switching key K, thus breaking the locking winding of the relay N. This restores the entire system to normal, and the attendantcan then cause a repetition of the starting of the charging mechanism by again depressing the switching key K, whereupon the operations which have been previonsly described, will again take place if the source of trouble in the charging mechanism is still effective. The attendant can then observe what the trouble is, and upon remedying same, can, by restoring the switching key K, start the charging operation in the regular way, when the dynamo-electric machine will start to charge the storage battery. When this occurs previous to the moment when ,the locking relay N has operated, the emergency circuit, as has been previously described as being closed by armature 100 making contact with the contact piece 101 whenever the armature is in the released or normal position, will now be opened by the breaking away from the contact piece 101 by armature 100. Therefore, the differential winding 105 of the relay M will not be energized and therefore, the relay M will remain energized. Thus the charging operation will go on until the accumulator is chargedto a predetermined amount. Whenever this occurs, the movable needle 11 of the electro-responsive device G will be caused to make a contact with contact piece 47 when the following circuit will be closed :.positive pole-of batterycontacts 13 and 14 of the switching key K conductors 151622movable needle 11 -contact 47-contact piece 115and lever arm 116 of the switch 'flr-COIldllCtOI' 117- winding 118 of the relay Oconductor 119 contact piece 120 and armature 44 of the relay M'conductor 121alarm device a conductors 11210730-29-28'contact piece 24 and armature 23 of the relay O conductor 27contacts 26 and 25 of the switching key K to negative battery. The winding 118 of the relay 0 is so connected as to oppose the action of winding 18 of this relay, both windings being preferably of very high resistance, and therefore, upon both of them being energized. as is found in the case when in opposition one to the other, the relay 0 will'release its 'armatures 2O and 23, which break connection with the contact pieces 21 and 24 respectively, thus restoring the entire system to normal, since the breaking of contact 24 by the armature 23 releases the relay M, which in turn opens the circuit of the winding 118. a

In the foregoing description of the emergency circuit so-called, I neglected to state that the effect of the closing of this circuit by the connection of armature 100 to contact 101 of the relay L can also be produced by the operation of the devices Y, Y, Z and Z, which devices indicate, in the cases of Y and Y the lack of lubricating oil or of water for cooling the engine cylinder, or in the case of Z and Z, that some bearing or moving part of the charging mechanism has become toohot. Therefore, any one of these devices, by closing its electrical contact, can close the emergency circuit and shut down the charging mechanism in the same way as has been previously described as being done by the release of armature of the relay L, it being shown in the drawing that the contacts of all these devices are connected in multiple one'with the other and in multiple with the switch controlled by the relay L. The devices Y and Y are similar and consist of floats 1 and F immersed in their lGSPfict-lX'e liquids. Arms 41, and 0, are here shown so fastened to the floats F and F that whenever these floats are lowered, due to a lowering in the level of the liquids, the arms a and 0, will force spring contacts 122 and 123 in the case of Fiend spring contacts 121- and'125 in the case of 1 together, making connection between the common wires 126 and 127 The thermostats Z and Z consist each of two members riveted together a manner similar to the riveted members of the device it, only, that as shown in the drawing, the two kinds of material. used are transposed; that is, in Z and Z the more expansible material is placed the bottom and the less expansible on top of the two riveted members, so that when heating, the direction of movement of the ends 132 and 133 will be up-,

ward, it being understood that. the other ends of these members are fastened to a fixed support, not shown. Under these conditions, contacts will be made in the one case between the end 132 of the thermostat and the contact piece 130, thus closing a circuit between the wires 126 and 127. in other case, the end 183 of the thermostat Z will make contact with the contact piece 131 in a similar manner, closing a circuit between the common Wires 126 and 127, as before described.

Since it is understood that any of the emergency devices Y and Y and Z and Z are capable of closing a circuit when operated, between the common wires 126 and 127, under the conditions of operation of any one of these devices, the following circuit is closed :positive batteryconductor 42 armature 11 and contact piece 99 of the relay N-conductor 1,02conductor 129common wire 126 through the contact piece and movable member of whichever emergency devices happens to be operated, to common wire 127conductors 128103 10i-- winding or the relay M conductors 106107 3029-28contact piece 23 and armature 2 1 of the relay Ocontact pieces 26 and 25 ot' the switching key K to negative battery, thus closing the emergency circuit which has previously been mentioned and described, and causing the release of the charging mechanism and the operation of the alarm devices, as has previously been described.

The switch 6 when thrown to a position 131 instead 115, causes the termination, of the char ing period to be determined by a floating hydrometer it, shown more 1n detail in Fig. 2, having an arm a adapted to force the spring contacts 135 and 136 ipeclfic 2928contact piece and armature O of the relay @contacts 26 and of the switching key-K to negative battery.

The winding 118, as has been previously mentioned, is so connected as to oppose the action of winding 118, thus releasing the armatures of the relay whereupon the entire circuit will be restored to normal in the same manner as was previously described in connection with the shutting down of the charging mechanism by the action of the movable needle 11.

In Fig. 3 is shown a method whereby, at times, the operator of the system can control the charging operation entirely by the action of such a floating hydrometer as has been previously described. At if is shown such a hydrometer device having an arm a adapted to force, when in one position of use depending upon the degree of discharge of the storage battery, the switch contacts 1;

138 and 139 together, and when in another position of use, depending upon the extent of the charging of the storage battery, adapted to force the switch contacts 14:0 and 141 together. These spring contacts may be mounted on a floating member 1 12, which floating member depends almost entirely upon the height of the liquid in the battery in contradistinction to the hydrometer device 76 which depends on the height of the liquid and more particularly to the specific gravity of the liquid. This dlfierence can be caused by the proportionspring contact ing of the two members as to their surface I dimensions. The circuits controlled by the closing of these contacts are the same as would be controlled by the movable needle 11 in the ordinary use of the system, the only diii'erence being that when the hy meter device if is used, the contact springs 1 10 and 141 are substituted for the contact 17 and the movable needle 11, and the contact springs 139 and 138 are also substituted for the contact piece 12 and movable needle in the circuit, and also, the hydrometer device if being used, there is no need of the use of the contact pieces and movable member of the device G, nor the device G itself and also the resistances 1 and 1" related thereto.

The discharge circuit of the storage battery B is as follows :positive pole of the battery Bconductor 62brush member 146 resting upon the commutator of the dynamo Da low resistance winding on the armature of the dynamo D, not shownto a brush member 147 also resting upon the commutator of the dynamo D and separated from the brush'member 146 a certain distance which is predetermined for the reason later to be described-then either of conductors 2 or 3through the electro-responsive devices Ethrough conductors 1 or 4 to negative pole of battery B. It is understood that switches for interrupting' the circuit of any or all of the lamps shown at E may be provided, the drawing.

It is seen that when the system is at rest, currents for the electro-responsive devices E are compelled to traversev a certain portion of the conductors on the armature of the dynamo D, and an adjustment can be made whereby, due to the very low resistalthough not shown in ance of said conductors, there will be very little loss of energy, due to such resistance.

brushes 146 and 147 there will be a certain potential difference, and that such potential difierence will be a fraction of the potential difference existing between the brushes 146 and 148; also that such potential difference as may exist between brushes 146 and 147 willbe in opposition so far as the electroresponsive devices E are concerned, to the potential of the battery B and will be subtracted therefrom so that the electro-responsive devices E will receive a potential during the charging operation equal to the difference between the potential of the battery being charged, and the potential between the brushes 146 and 147. Therefore, inasmuch as the battery when it is being charged is apt to have an excessive potential which might considerably "shorten the life and be otherwise injurious to the electro-responsive devices E, particularly it these devices consist in part of incandescent lamps, the counter-potential introduced into the circuit during thecharging operation by the spaced brushes 146 and 1 47 counter-acts the effect of the increased potential of the battery and keepsthe potentialat the lamps reasonably near a constant value. automatic system of this kind, it is sometimes imperative that automatic means to produce this result be provided. In manual systems, various means are provided for the same purpose, operated by the attendant manually. One of the objects of thls invention is to provide reliable automaticmeans for accomplishing this purpose. It

is understood that while I have shown specific means and specific methods of operating these means to produce certain results,

In an I do not wish to confine myself to the same,

as it will be evident to those skilled in the art that numerous and extensive departures may be made from the details of the embodiment of my invention as described, without departing from the spirit of the invention.

What I claim is 1. In an electric system, a charging mechanism, an accumulator, means for connecting said accumulator to said charging mechasaid accumulator to said charging mechanism, a plurality of controlling devices for said means and-selective means for said controlling devices, one of said controlling devices consisting of a marginal relay and another of a device depending for its operation upon the condition of the electrolyte in the accumulator.

2. In an electric system, the combination of a dynamo-electric machine, aprime mover connected thereto, anaccumulator, a circuit for connecting said accumulator to said dynamo-electric machine, electrically controlled mechanism controlling the circuit of said accumulator,"a pluralityof controlling means governing said mechanism and a selecting device for said controlling means, one of said controlling means consisting of a voltmeter relay and the other of anhydrometer in the electrolyte of the accumulator, and an electric switch controlled thereby.

3. In an electric system, a dynamo-electric machine, an accumulator adapted to be charged thereby, a circuit for connecting said dynamo-electric machine to said accumulator, said circuit being normally open, means to close said circuit, a voltmeter relay controlling said means, and adapted to be operated to condition .the same to close said circuit, a hydrometer in the electrolyte of the accumulator, and means governed by said hydrometer controlling said circuit controlling means and adapted to condition same to open said circuit when the electrolyte in the accumulator reaches a predetermined condition.

1 nism, means controlling the connection of 4. In combination, a time element device,

a storage battery, a dynamo-electric machine adapted to charge said storage battery, means for controlling the operation of said dynamo electric machine and said time element device, mechanism controlling said controlling means and conditioning it for simultaneously causlng'the operation of said dynamoelectric machine and said time element desaid time element device limiting the period of operation of the alarm device, as above described.

5. In an electric system, a charging mechanism, an accumulator, means for connecting said accumulator to said charging mechanism and disconnecting said accumulator from said charging mechanism, means controlling the connection of said accumulator to said charging mechanism, a plurality of controlling devices for said means and selective means for said controlling devices, one of said controlling devices consisting of a marginal relay and another of a device dependent for its operation upon the condition of the electrolyte inthe accumulator.

6. In an electric system, the combination of a dynamo electric machine, a prime mover connected thereto, an accumulator, a circuit for connecting said accumulator to said dynamo-electric machine, electrically controlled mechanism controlling the circuit of said accumulator for connecting and disconnecting said accum ilator and dynamo-electric machine, a plurality of controlling means governing said mechanism and a selective device for said controlling means, one of said controlling means consisting of a voltmeter relay and another of a hydrometer in the electrolyte of the accumulator, and an electric switch controlled thereby.

In testimony whereof, I aflix my signature in the presence of two Witnesses.

FRANK M. SLOUGH. Witnesses:

GEORGE E ROBERTS, R. G. SANDS. 

